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Setting up speakers

Despite post #57, still had 'vocals left of centre' effect so this w/end was measuring impedance of mid drivers with impedance flattening and notch filter in place to see if there were any differences and then noticed that the capacitive shunt of the cross-over of the right speaker (2.5µF composed from 1µF and 1.5µF in parallel) had one of these caps disconnected. Re-connected and had a quick listen - much better. Measured voltages across all the components of both L and R mids with a 1kHz test tone (just in case) and these were within spitting distance of each other. Note to self: need to be more careful!
 
Despite even the above, still wasn't happy with the 'vocals left of centre' effect and was looking around the room. As I am firing diagonally, I have a 'clear' corner to the left (where the room door is situated) and a 'dirty' corner to the right which has a coffee table with some speakers perched on it. Moved the speakers and hey-presto vocals more centred with better overall imaging and focus, presumably due to an earlier reflection from r/h side than l/h side! Only had about an hour like this but hopefully will get some listening in at the weekend.
 
Well-well, more than 1 year later.....
Lots of tweaking / messing around, but Friday it sounded Shi7e. And I mean shi7e, massive hole right-of centre, no detail, just awful. Remembered back to when I'd had something similar before so got a straight-edge out and measured the upper baffle (with mid and tweet on) in relation to the lower baffle, where the bass is mounted. Left speaker upper baffle measured 37mm behind bass baffle. Right speaker, top was 38mm behind, bottom was 37mm behind. 1mm in about 250mm high is about 0.25 degree angle. Put a card shim under the back of the baffle (so it measured 37mm top and bottom) and hey-presto! Now have a much better rendered central image. Just shows how fussy a 3-way arrangement is when it comes to integration! And it shows how much can be masked without realising as the previous week it sounded pretty much ok but with the vocals still biased a bit to the left.
 
Well another six months gone. Where does it go....? Was listening yesterday and despite previous improvements, still felt there was 'something missing' esp in the mids. Whilst looking at the speakers it 'clicked': the wiring from the x-over to the bass units is single strand, hanging loosely and untwisted with about 3" free space between them. I twisted them loosely together and hey presto: more mid range detail and improved image depth and placement.
 
Changing the CD160 has improved the hf texture and detail so much that this has lead to me needing to make a small mod to the speaker crossovers. I'd been playing with impedance flattening on the mid driver which has 2.2uF in series with 17R with wires to the cap to allow an extra 1uF to be switched in/out from the listening position. I'd pretty much come to the conclusion that it was a bit too forward with 2.2uF and was better with the extra 1uF, but a bit too bright after the change to the CD160. I'd found a long time ago now that some 3.3uF Monacor pp caps were a bit dull on the tweeters (replaced with 3.3uF silver Z cap) so thought that these might be just right in this impedance flattening role. What a pleasant surprise. This is now so much better, with a much better tonal balance, including a perceived improvement in the l/r coherence. More listening still to do, but overall massive improvement. :)
 
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